Premium
Kinetic and solvent isotope effects on biotransformation of aromatic amino acids and their derivatives
Author(s) -
Kańska Marianna,
Jemielity Jacek,
Pająk Małgorzata,
Pałka Katarzyna,
Podsadni Katarzyna,
Winnicka Elżbieta
Publication year - 2016
Publication title -
journal of labelled compounds and radiopharmaceuticals
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.432
H-Index - 47
eISSN - 1099-1344
pISSN - 0362-4803
DOI - 10.1002/jlcr.3419
Subject(s) - chemistry , biotransformation , kinetic isotope effect , organic chemistry , solvent , amino acid , environmental chemistry , biochemistry , enzyme , deuterium , physics , quantum mechanics
Aromatic amino acids such as l ‐phenylalanine, l ‐tryptophan, 3′,4′‐dihydroxy‐ l ‐phenylalanine ( l ‐DOPA), and their derivatives 3′,4′‐dihydroxyphenylacelaldehyde (DOPAL) and 3′,4′‐dihydroxyphenylethanol (DOPET), play an essential role in human metabolic processes. Incorrect or slow biotransformation of these compounds leads to some metabolic dysfunctions and in some cases to some neurodegenerative diseases. Therefore, studies of the biotransformation mechanisms of these metabolites draw biochemists' and medical researchers' attention. This study investigates the mechanisms of biotransformation of the aforementioned compounds using kinetic (KIE) and solvent (SIE) isotope effect methods. The overview presents the results and the numerical values of KIE and SIE methods, obtained in the study of biotransformation of l ‐phenylalanine, 5′‐chloro‐ l ‐tryptophan, and l ‐DOPA, catalyzed by the enzymes from the lyases group (phenylalanine ammonia lyase, tryptophan indole‐lyase, and tyrosine decarboxylase). Deuterium KIE was also determined during the deamination of 2′‐chloro‐ l ‐phenylalanine in the presence of the enzyme l ‐phenylalanine dehydrogenase, as well as in the conversion of DOPAL into DOPET catalyzed by the enzyme alcohol dehydrogenase. The values of KIE and SIE have been determined using a noncompetitive spectrophotometric and a competitive (combined with internal radioactivity standard) radiometric methods.